(a) Field
Embodiments of the present invention relate to an organic light emitting diode (OLED) display and a driving method thereof.
(b) Description of the Related Art
In general, with respect to flat panel displays, there are a liquid crystal panel display, a field emission panel display, a plasma display panel (PDP), and an organic light emitting diode (OLED) display.
Among the flat organic light emitting diode (OLED) displays, the organic light emitting diode (OLED) display using an organic light emitting diode (OLED) means a flat display using an electro-luminescence phenomenon of an organic material. The organic light emitting diode emits light using a mechanism in which electrons and holes are injected from electrodes and the injected electrons and holes are combined to have an excitation state.
The organic light emitting diode display can have reduced volume and weight because an additional light source is not required, and it may be used for an electronic product such as a portable terminal or a large-sized television with characteristics such as relatively low power consumption, high luminous efficiency, high luminance, and a wide viewing angle, as well as a fast response speed.
The organic light emitting diode (OLED) display includes a data driver transmitting a data signal to a plurality of data lines, a scan driver sequentially transmitting a scan signal to a plurality of scan lines, and a plurality of pixels coupled to a plurality of scan lines and a plurality of data lines. Each pixel supplies a current corresponding to the corresponding data signal to the organic light emitting diode (OLED), and the organic light emitting diode (OLED) emits light according to the supplied current amount.
When increasing the number of pixels to improve the resolution of the organic light emitting diode (OLED) display, a plurality of pixels coupled to one scan line are coupled to different data lines such that the number of data lines is proportionally increased. Accordingly, the circuit of the data driver may be relatively complicated and the manufacturing costs of the data driver may be relatively high.
To reduce the complexity and manufacturing costs of the data driver, a demultiplexer may be utilized, which selectively outputs one input signal to one among a plurality of output lines. That is, by sequentially applying the data signal output from the data driver to a plurality of data lines through the demultiplexer of a 1:n method, the circuit of the data driver may be simplified.
As described above, for the organic light emitting diode (OLED) display using the demultiplexer, to prevent the data signal input to each pixel during current horizontal period from being influenced by the data signal applied during the previous horizontal period, each horizontal period is divided into a writing period in which the data signal is written and a scan period in which the data signal is transmitted to each pixel according to the scan signal.
However, as the organic light emitting diode (OLED) display is developed with higher resolution, a horizontal period is decreased such that the writing of the data to all pixels through the 1:n demultiplexer is limited. For this, when increasing the data writing period, the scan period is relatively shortened. Accordingly, the data compensation time is shortened such that spots may be generated in the display.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.